In recent years, various technologies have been developed to increase storage capacity in magnetic disk devices. In one of the technologies, magnetic disk devices use shingled magnetic recording (SMR) to write data. The shingled magnetic recording is a recording system for writing data such that the current track partially overlaps the previously written adjacent track (hereinafter, simply referred to as the adjacent track). When magnetic disk devices write data by shingled magnetic recording, the track density (tracks per inch: TPI) of disks can be improved in comparison with normal recording (normal magnetic recording).
Magnetic disk devices used for shingled magnetic recording set a recording area for writing data by shingled magnetic recording and a recording area for writing data by normal recording. When data is written, magnetic disk devices may have the effect of fringing on the adjacent tracks. In shingled magnetic recording, the direction in which data is written is determined. Thus, the effect of fringing from only one of the two tracks adjacent to the target track should be taken into consideration. Therefore, the track pitch between the target track and the adjacent track can be narrow. In normal recording, in consideration of the effect of fringing from the two tracks adjacent to the target track, it is necessary to set the track pitch between the target track and the two adjacent tracks so as to be great.